#include "../test_helpers.hxx"
#include "../test_types.hxx"

#include <pqxx/stream_from>

#include <cstring>
#include <iostream>
#include <string>
#include <tuple>
#include <vector>

#include <optional>


namespace
{
void test_nonoptionals(pqxx::connection_base& connection)
{
  pqxx::work tx{connection};
  pqxx::stream_from extractor{tx, "stream_from_test"};
  PQXX_CHECK(extractor, "stream_from failed to initialize");

  std::tuple<
    int,
    std::string,
    int,
    ipv4,
    std::string,
    bytea
  > got_tuple;

  extractor >> got_tuple;
  PQXX_CHECK(extractor, "stream_from failed to read first row");
  PQXX_CHECK_EQUAL(std::get<0>(got_tuple), 1234, "field value mismatch");
  // PQXX_CHECK_EQUAL(*std::get<1>(got_tuple), , "field value mismatch");
  PQXX_CHECK_EQUAL(std::get<2>(got_tuple), 4321, "field value mismatch");
  PQXX_CHECK_EQUAL(
	std::get<3>(got_tuple),
	(ipv4{8, 8, 8, 8}),
	"field value mismatch");
  PQXX_CHECK_EQUAL(
	std::get<4>(got_tuple),
	"hello world",
	"field value mismatch");
  PQXX_CHECK_EQUAL(
	std::get<5>(got_tuple),
	(bytea{'\x00', '\x01', '\x02'}),
	"field value mismatch");

  try
  {
    extractor >> got_tuple;
    PQXX_CHECK_NOTREACHED("stream_from improperly read second row");
  }
  catch (const pqxx::conversion_error &e)
  {
    std::string
        what{e.what()},
        expected{"Attempt to convert null to " + pqxx::type_name<int> + "."};
    if (what != expected) throw;
    pqxx::test::expected_exception("Could not extract row: " + what);
  }

  std::tuple<
    int,
    std::string,
    std::nullptr_t,
    std::nullptr_t,
    std::string,
    bytea
  > got_tuple_nulls1;
  std::tuple<
    int,
    std::nullptr_t,
    std::nullptr_t,
    std::nullptr_t,
    std::string,
    bytea
  > got_tuple_nulls2;

  try
  {
    extractor >> got_tuple_nulls2;
    PQXX_CHECK_NOTREACHED("stream_from improperly read second row");
  }
  catch (const pqxx::conversion_error &e)
  {
    if (std::string{e.what(), 27} != "Attempt to convert non-null") throw;
    pqxx::test::expected_exception(
      std::string{"Could not extract row: "} + e.what()
    );
  }

  extractor >> got_tuple_nulls1;
  PQXX_CHECK(extractor, "stream_from failed to reentrantly read second row");
  extractor >> got_tuple_nulls2;
  PQXX_CHECK(extractor, "stream_from failed to reentrantly read third row");
  extractor >> got_tuple;
  PQXX_CHECK(not extractor, "stream_from failed to detect end of stream");

  extractor.complete();

  PQXX_CHECK_SUCCEEDS(
	tx.exec1("SELECT 1"),
	"Could not use transaction after stream_from.");
}


void test_bad_tuples(pqxx::connection_base &conn)
{
  pqxx::work tx{conn};
  pqxx::stream_from extractor{tx, "stream_from_test"};
  PQXX_CHECK(extractor, "stream_from failed to initialize");

  std::tuple<int> got_tuple_too_short;
  try
  {
    extractor >> got_tuple_too_short;
    PQXX_CHECK_NOTREACHED("stream_from improperly read first row");
  }
  catch (const pqxx::usage_error &e)
  {
    std::string what{e.what()};
    if (what != "Not all fields extracted from stream_from line") throw;
    pqxx::test::expected_exception("Could not extract row: " + what);
  }

  std::tuple<
    int,
    std::string,
    int,
    ipv4,
    std::string,
    bytea,
    std::string
  > got_tuple_too_long;
  try
  {
    extractor >> got_tuple_too_long;
    PQXX_CHECK_NOTREACHED("stream_from improperly read first row");
  }
  catch (const pqxx::usage_error &e)
  {
    std::string what{e.what()};
    if (what != "Too few fields to extract from stream_from line.") throw;
    pqxx::test::expected_exception("Could not extract row: " + what);
  }

  extractor.complete();
}


#define ASSERT_FIELD_EQUAL(OPT, VAL) \
  PQXX_CHECK(static_cast<bool>(OPT), "unexpected null field"); \
  PQXX_CHECK_EQUAL(*OPT, VAL, "field value mismatch")
#define ASSERT_FIELD_NULL(OPT) \
  PQXX_CHECK(not static_cast<bool>(OPT), "expected null field")


template<template<typename...> class O>
void test_optional(pqxx::connection_base& connection)
{
  pqxx::work tx{connection};
  pqxx::stream_from extractor{tx, "stream_from_test"};
  PQXX_CHECK(extractor, "stream_from failed to initialize");

  std::tuple<int, O<std::string>, O<int>, O<ipv4>, O<std::string>, O<bytea>>
	got_tuple;

  extractor >> got_tuple;
  PQXX_CHECK(extractor, "stream_from failed to read first row.");
  PQXX_CHECK_EQUAL(std::get<0>(got_tuple), 1234, "Field value mismatch.");
  PQXX_CHECK(
	static_cast<bool>(std::get<1>(got_tuple)), "Unexpected null field.");
  // PQXX_CHECK_EQUAL(*std::get<1>(got_tuple), , "field value mismatch");
  ASSERT_FIELD_EQUAL(std::get<2>(got_tuple), 4321);
  ASSERT_FIELD_EQUAL(std::get<3>(got_tuple), (ipv4{8, 8, 8, 8}));
  ASSERT_FIELD_EQUAL(std::get<4>(got_tuple), "hello world");
  ASSERT_FIELD_EQUAL(std::get<5>(got_tuple), (bytea{'\x00', '\x01', '\x02'}));

  extractor >> got_tuple;
  PQXX_CHECK(extractor, "stream_from failed to read second row");
  PQXX_CHECK_EQUAL(std::get<0>(got_tuple), 5678, "field value mismatch");
  ASSERT_FIELD_EQUAL(std::get<1>(got_tuple), "2018-11-17 21:23:00");
  ASSERT_FIELD_NULL(std::get<2>(got_tuple));
  ASSERT_FIELD_NULL(std::get<3>(got_tuple));
  ASSERT_FIELD_EQUAL(std::get<4>(got_tuple), "こんにちは");
  ASSERT_FIELD_EQUAL(
	std::get<5>(got_tuple),
	(bytea{'f', 'o', 'o', ' ', 'b', 'a', 'r', '\0'}));

  extractor >> got_tuple;
  PQXX_CHECK(extractor, "stream_from failed to read third row");
  PQXX_CHECK_EQUAL(std::get<0>(got_tuple), 910, "field value mismatch");
  ASSERT_FIELD_NULL(std::get<1>(got_tuple));
  ASSERT_FIELD_NULL(std::get<2>(got_tuple));
  ASSERT_FIELD_NULL(std::get<3>(got_tuple));
  ASSERT_FIELD_EQUAL(std::get<4>(got_tuple), "\\N");
  ASSERT_FIELD_EQUAL(std::get<5>(got_tuple), bytea{});

  extractor >> got_tuple;
  PQXX_CHECK(not extractor, "stream_from failed to detect end of stream");

  extractor.complete();
}


void test_stream_from()
{
  pqxx::connection conn;
  pqxx::work tx{conn};
  tx.exec(
    "CREATE TEMP TABLE stream_from_test ("
    "number0 INT NOT NULL,"
    "ts1     TIMESTAMP NULL,"
    "number2 INT NULL,"
    "addr3   INET NULL,"
    "txt4    TEXT NULL,"
    "bin5    BYTEA NOT NULL"
    ")"
  );
  tx.exec_params(
    "INSERT INTO stream_from_test VALUES ($1,$2,$3,$4,$5,$6)",
    1234,
    "now",
    4321,
    ipv4{8, 8, 8, 8},
    "hello world",
    bytea{'\x00', '\x01', '\x02'}
  );
  tx.exec_params(
    "INSERT INTO stream_from_test VALUES ($1,$2,$3,$4,$5,$6)",
    5678,
    "2018-11-17 21:23:00",
    nullptr,
    nullptr,
    "こんにちは",
    bytea{'f', 'o', 'o', ' ', 'b', 'a', 'r', '\0'}
  );
  tx.exec_params(
    "INSERT INTO stream_from_test VALUES ($1,$2,$3,$4,$5,$6)",
    910,
    nullptr,
    nullptr,
    nullptr,
    "\\N",
    bytea{}
  );
  tx.commit();

  test_nonoptionals(conn);
  test_bad_tuples(conn);
  std::cout << "testing `std::unique_ptr` as optional...\n";
  test_optional<std::unique_ptr>(conn);
  std::cout << "testing `std::optional` as optional...\n";
  test_optional<std::optional>(conn);
}


PQXX_REGISTER_TEST(test_stream_from);
} // namespace
